Multistatic multibeam signal processing approaches with applications in fish farming

Aquaculture food production grows faster than other major food production sectors, and in the Faroe Islands, salmon accounts for nearly half of the countries export value. In order to to keep up width the global trend, fish-farming in the Faroe Islands has moved from sheltered locations, to more exposed farming sites. Understanding the behaviour offish-farming equipment and their inhabitants at exposed sites is important for ensuring fish welfare, and by extension, profits.
Measurement equipment and methods make used today make it difficult to obtain an accurate description of the cage and the fish distribution and movement, since the cages are very large and in exposed sites are subject to large deflections and deformations. Typical Sonars have a comparatively high range, compared to optical cameras, but lack the ability to measure in different directions. Multibeam sonars allow for spatial information of its surroundings to be gathered, but suffer from side-lobe interference at distances longer than the distance to large surfaces, such as the water surface. This issue, can largely be mitigated by using multiple multibeam sonars, running in a multistatic configuration. The aim of this project is to develop a multistatic multibeam system and methods to collect and extract spatial information about the extent of the cage, and the distribution of the biomass within. These methods can be used to get a better understanding of the behaviour of fish farming equipment and its inhabitants